2x-3=4k
2x=4k+3
x=(4k+3)/2
(x-k)/2=k-3x
x-k=2k-6x
7x=3k
x=3k/7
∴(4k+3)/2=3k/7
7(4k+3)=6k
28k+21=6k
28k-6k=-21
22k=-21
k=-21/22